Single-stranded DNA binding protein Gp5 of Bacillus subtilis phage Φ29 is required for viral DNA replication in growth-temperature dependent fashion.

In the absence of viral single-stranded DNA binding protein gp5, Bacillus subtilis phage φ29 failed to grow and to replicate its genome at 45 °C, while it grew and replicated normally at 30 °C and 42 °C. This indicates that gp5 is dispensable for φ29 DNA replication at 42 °C and lower temperatures.